The following background description is not an admission that any apparatus or method discussed below is prior art or part of the knowledge of people skilled in the art in any country.
U.S. Pat. No. 4,960,019 describes a stationary steel rule cutting die for cutting a fixed pattern in each of a plurality of stacked compressible material layers according to the shape of the steel rule die and including a vacuum system for reducing the stacked height of the compressible material layers prior to cutting. The die assembly includes an enclosure comprising an upper wall and collapsible side walls extending downwardly from the upper wall. A rigid annular structure is secured to the lower edge of the collapsible side walls. The enclosure is positioned over the stacked compressible material layers with an annular sealing surface defined on the lower peripheral edges of the rigid annular structure coacting with an upwardly facing, closed loop sealing surface defined on the steel rule cutting die to define a sealed chamber from which air is exhausted through the rigid annular structure to collapse the side walls of the enclosure and compress the material layers prior to cutting.
In U.S. Pat. No. 6,233,809, a cutting knife assembly has a baseboard with a generally planar surface. A cutting knife is detachably connected to the baseboard. The cutting knife extends in a perpendicular direction to the baseboard. The cutting knife circumscribes a knife cavity on the baseboard. At least one elongated cross member is affixed to the cutting knife and extends across the knife cavity. The cross member is mounted to the baseboard by a removable fastener. The cutting knife may then be easily removed from the baseboard and resecured.
U.S. Pat. Nos. 4,960,019 and 6,233,809 are incorporated herein, in their entirety, by this reference to them.